A usability analysis method of a web application including: a first step of acquiring a page transition log and operation logs on individual pages in the web application; a second step of detecting a segment having a specific page transition pattern in the page transition log; a third step of managing operation logs on individual pages included in the detected page transition pattern in relation to the individual pages; a fourth step of performing statistic processing on the managed operation logs and analyzing page utilization; and a fifth step of analyzing usability based on the page transition pattern and the page utilization.
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1. A usability analysis method of a web application, comprising:
acquiring a page transition log and operation logs on individual pages in the web application;
referring to a transition pattern detection rule table holding a sequence of urls as a specific page transition pattern including multiple occurrences of a same page, to detect the specific page transition pattern in the page transition log;
managing the operation logs on individual pages included in the detected specific page transition pattern, in relation to the individual pages in order of appearance;
performing statistic processing on the managed operation logs and analyzing page utilization; and
analyzing usability based on the specific page transition pattern and the page utilization;
wherein the analyzing includes acquiring a workflow definition defining a work procedure provided by the web application,
wherein the transition pattern detection rule table includes a transition pattern different from a page transition pattern following the workflow definition,
wherein the referring refers to the transition pattern detection rule table to detect the different transition pattern in the page transition log, in a case where pages are changed in the transition pattern different from the page transition pattern following the workflow definition, and
wherein the analyzing analyzes usability based on the different page transition pattern and the page utilization.
6. An analysis server for analyzing usability of a web application provided to a client device, the analysis server comprising:
at least one processor and memory, configured to:
manage a transition pattern detection rule table holding a sequence of urls as a specific page transition pattern including multiple occurrences of a same page;
compare page transition logs with the transition pattern detection rule table to detect the specific transition pattern in the page transition logs;
acquire and record operation logs on individual pages in the detected specific transition pattern in log management information, in relation to the individual pages in order of appearance;
perform statistic processing on the managed operation logs and analyze page utilization; and
analyze the web application based on the specific transition pattern and the page utilization;
wherein the analyzing includes acquiring a workflow definition defining a work procedure provided by the web application,
wherein the transition pattern detection rule table includes a transition pattern different from a page transition pattern following the workflow definition,
wherein the managing refers to the transition pattern detection rule table to detect the different transition pattern in the page transition log, in a case where pages are changed in the transition pattern different from the page transition pattern following the workflow definition, and
wherein the analyzing analyzes usability based on the different page transition pattern and the page utilization.
8. A non-transitory, computer-readable medium embodying a program executed in an analysis server for analyzing usability of a web application provided to a client device, the program being configured to cause the analysis server to perform:
acquiring a page transition log and operation logs on individual pages in the web application;
referring to a transition pattern detection rule table holding a sequence of urls as a specific transition pattern including multiple occurrences of a same page, to detect the specific page transition pattern in the page transition log;
managing the operation logs on individual pages in the detected specific transition pattern, in relation to the individual pages in order of appearance;
performing statistic processing on the managed operation logs and analyzing page utilization; and
analyzing usability based on the specific transition pattern and the page utilization;
wherein the analysis server is caused to manage a workflow definition defining a work procedure provided by the web application,
wherein the transition pattern detection rule table includes a transition pattern different from a page transition pattern following the workflow definition, and
wherein the referring refers to the transition pattern detection rule table to detect the different transition pattern in the page transition log, in a case where pages are changed in the transition pattern different from the page transition pattern following the workflow definition, and
wherein the analyzing analyzes usability based on the different page transition pattern and the page utilization.
2. The usability analysis method according to
3. The usability analysis method according to
determining priority degrees of results of the analysis in accordance with the policy definition; and
controlling order of displaying the results of the analysis based on the determined priority degrees, and outputting the results of the analysis.
4. The usability analysis method according to
wherein the first condition of the policy definition is that a rate of returning of a page to a previous page is equal to or higher than a predetermined threshold, and
wherein the second condition of the policy definition is that a staying time of a page is equal to or less than a predetermined threshold, or that a perusal rate of the page is equal to or lower than a predetermined threshold.
5. The usability analysis method according to
wherein the different transition pattern includes information indicating a page transition in a direction reverse to a direction of a page transition following the workflow definition.
7. The analysis server according to
9. The non-transitory, computer-readable medium according to
wherein the analysis server is caused to manage policy definitions for utilization analysis, including a first condition with regard to page transition patterns and a second condition with regard to page utilization, and
wherein the analyzing analyzes usability using the policy definitions for utilization analysis, including the first condition with regard to page transition patterns and the second condition with regard to page utilization.
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This invention relates to a method for usability analysis of web applications and, in particular, relates to a technique for analyzing usability of a web application which involves page transitions based on a workflow.
In recent years, a variety of services and works have been implemented in web applications. Improvement in performance of client terminals and server devices and advancement in web technologies, as seen in AJAX (Asynchronous JavaScript+XML), have brought web applications involving not simple page transitions, represented by Google Maps, into practical use.
Furthermore, an approach to supporting routine works that follow predetermined procedures has been tried with web applications. Such a web application provides a flowchart image for indicating a workflow and a guide image for supporting operations at each step of the workflow. A user manipulates the guide image, following the workflow indicated in the flowchart image, to pursue the routine work.
In general, it is demanded for a web application that even a user with low IT literacy can make full use of it. The usability level of the web application significantly affects working efficiency; therefore, high usability is demanded for a web application.
The first thing to improve the usability of a web application is to grasp the actual conditions. The next thing is to analyze the conditions to improve the web application based on the result of the analysis. To grasp the conditions, there are two techniques: determining page transitions and determining utilization of pages.
To determine page transitions, there exist several techniques: a technique to determine whether a user is lost the way in page transitions (refer to JP 2003-281317 A), a technique to determine a route accessed with high frequency (refer to JP 2004-152209 A), and a technique to check whether pages are accessed as desired by the producer (refer to JP 2002-123516 A).
Patent Literature 1: JP2003-281317A
Patent Literature 2: JP2004-152209A
Patent Literature 3: JP2002-123516A
The techniques disclosed in JP2003-281317A, JP2004-152209A, and JP2002-123516A are to be applied to web applications which simply repeat page transitions. For this reason, it was sufficient that they merely determine the utilization of pages or transitions of pages. In the case of a web application involving page transitions based on a workflow, however, it is necessary to consider the relationship between page transitions leading to the efficiency of the workflow and utilization of pages leading to the efficiency of operations at work steps in the workflow.
To improve the usability, the following operations with logs indicating page utilization by a plurality of users and page transitions are required: (1) detecting transition patterns which are likely to be problems (such as returning, repeating, jumping, and rerouting) from the page transition patterns (routes), (2) listing pages which are likely to be problems, and (3) analyzing the utilization of the pages (operation logs) through, for example, statistical processing. In particular, the operation of step (2) requires the pages to be extracted for each transition pattern. The same page may appear at a plurality of points in a transition pattern; then, the page must be regarded as different pages. This may happen in rerouting; a branch page appears twice: at the first branch and a branch under rerouting. These two branches should be regarded as different pages to be managed in consideration of the order of appearance in analyzing operation logs. Accordingly, it has been difficult for an inexperienced analyst to determine the usability of a web application within a short time by analyzing only operation logs.
This invention is to solve the aforementioned problem and an object of this invention is to provide a method for usability analysis of web applications which can reliably analyze the usability of a web application involving page transitions.
An representative example of the invention disclosed in this application is a usability analysis method of a web application including: a first step of acquiring a page transition log and operation logs on individual pages in the web application; a second step of detecting a segment having a specific page transition pattern in the page transition log; a third step of managing operation logs on individual pages included in the detected page transition pattern in relation to the individual pages; a fourth step of performing statistic processing on the managed operation logs and analyzing page utilization; and a fifth step of analyzing usability based on the page transition pattern and the page utilization.
A representative embodiment of this invention provides reliable analysis on the usability of a web application in consideration of correlations between transitions and utilization of pages.
Hereinafter, an embodiment of this invention will be described with reference to the accompanying drawings. In this description, function blocks implemented by programs executed by processors in a computer system are expressed as modules or units.
Hereinafter, with reference to
System Configuration
The computer system 1 shown in
The client device 100 shown in
The I/O device 101 is an input device (such as a keyboard or a mouse) and an output device (such as a display device) for providing a user interface. The processor 102 executes a web browser program 105, a script engine program 106, and a not-shown OS (operating system) stored in the memory 104. The network interface 103 is a communication interface for the client device 100 to communicate data via the network 160. The memory 104 stores programs to be executed by the processor 102 and data to be used by these programs. The client device 100 may further include an external storage device (not shown).
The web server device 120 shown in
The network interface 121 is a communication interface for the web server device 120 to communicate data via the network 160. The processor 122 executes a web server program 127, a web application program 128, and a function inserting program 129 stored in the memory 126. Details of the operation of these programs will be described later. The web application program 128 in this description is a workflow-oriented web application program involving page transitions based on a workflow. The information defining the workflow is a workflow definition 124, which is held in the local disk 123. The workflow definition 124 is sufficient as long as it includes definition information of the workflow; it may be held in a different server such as a database server or a different storage device.
The local disk 123 is a storage device composed of, for example, a magnetic disk device and a non-volatile semiconductor memory. The local disk 123 may be mounted in the web server device 120 or may be an external storage device disposed outside the web server device 120.
The I/O device 125 is an input device (such as a keyboard or a mouse) and an output device (such as a display device) for providing a user interface. The web server device 120 does not need to have the I/O device 125. In such a case, the web server device 120 is operated by the client device 100. The memory 126 stores programs executed by the processor 122 and data used by these programs.
The log analyzing server device 140 shown in
The network interface 141 is a communication interface for the log analyzing server device 140 to communicate data via the network 160. The processor 142 executes a log server program 147, a log analyzing program 148, and a log visualizing program 149 stored in the memory 146. The local disk 143 is a storage device composed of, for example, a magnetic disk device and a non-volatile semiconductor memory; it stores a route management table 700, an operation log table 720, a log per transition pattern management table 1000, a current task operation log table 144, a transition pattern detection rule table 900, and a utilization analysis policy table 1200. The local disk 143 may be mounted in the log analyzing server device 140 or may be an external storage device disposed outside the log analyzing server device 140. Details of operations of the programs and configurations of the tables will be described later.
The I/O device 145 is an input device (such as a keyboard and a mouse) and an output device (such as a display device) for providing a user interface. The log analyzing server device 140 does not need to include the I/O device 145. In such a case, the log analyzing server device 140 is operated by a client device 100. The memory 146 stores programs to be executed by the processor 142 and data to be used by these programs.
Outline of Operation of Computer System 1
In response to a user operation to the web browser, the web browser module 200 sends a request 203 in accordance with the user operation. The request 203 is transmitted via a typical HTTP (Hyper Text Transfer Protocol) protocol, although the protocol for the request 203 is not limited to the HTTP protocol.
Upon receipt of the request 203, a web server module 220 requests a web application 221 relevant to the received request 203 to perform processing. The web application 221 performs processing in accordance with the request 203 to create a response 224 and transfers the created response 224 to a function inserting module 222. The function inserting module 222 incorporates an operation log acquiring module 223 into the transferred response 224 to create a response 225 and sends the created response 225 to the web browser module 200. The operation log acquiring module 223 is incorporated with a response filtering function included in the web server device 120, such as ServletFilter function of Java EE, ISAPI (Internet Server Application Programming Interface) filter function of IIS (Internet Information Services). In this embodiment, the operation log acquiring module 223 is dynamically incorporated by the function inserting module 222; however, the operation log acquiring module 223 may be incorporated in the web application 221 in advance, without using the function inserting module 222.
Upon receipt of the response 225 from the function inserting module 222, the web browser module 200 interprets the HTML (Hyper Text Markup Language) data in the received response 225 and displays the result on the web browser. It further transfers the operation log acquiring module 223 incorporated in the response 225 to a script engine module 201 (202). The operation log acquiring module 223 performs required initialization, and then, acquires information on the user operation on the web browser in the client device 100 in the form of an operation log. The web browser module 200 sends the operation log 205 acquired by the operation log acquiring module 223 to the log server module 240 in the log analyzing server device 140 when a page transition occurs to the web browser, for example. It should be noted that the page transition may be a page transition with or without communication via a network involved. The latter page transition without communication can be detected in rewriting a page in the web browser using a DOM (Document Object Model) or JavaScript technology.
Every time the log server module 240 receives an operation log 205 from the web browser module 200, the log server module 240 stores the received operation log 205 to the current task operation log table 144 (243). The current task operation log table 144 is a table for temporarily storing operation logs for a unit of work defined by the web application 221 being operated in the client device 100 (for example, from the start to the end of a workflow or from a log-in to a log-out, which is referred to as current task). When a current task is finished, information to be stored in the route management table 700 and the operation log table 720 is created based on the operation logs 205 held in the current task operation log table 144 and is appended to the tables.
The log analyzing module 241 integrally analyzes page transitions and user operations in individual pages based on the data held in the current task operation log table 144, the route management table 700, and the operation log table 720. The log visualizing module 242 visualizes problems in usability in accordance with the result of the analysis by the log analyzing module 241.
The log analyzing module 241 executes such processing responsive to an instruction from an administrative user or in a batch at an appropriate time.
Module Configuration of Log Analyzing Server Device 140
The log analyzing module 241 includes a page analysis unit 320, an operation analysis unit 321, and a utilization analysis unit 322. The page analysis unit 320 analyzes page transitions. Specifically, the page analysis unit 320 refers to the transition pattern detection rule table 900 to detect a specific transition pattern (such as return, repeat, jump, or reroute) which could be a problem. The operation analysis unit 321 analyzes user operation (such as a click of a mouse and typing in a form) on each page in the web browser. Concurrently, it manages related operation logs 300 for each transition pattern and each position in the order of appearance of pages in each transition pattern to analyze the operations. The utilization analysis unit 322 refers to the results of analysis by the page analysis unit 320 and the operation analysis unit 321 and policy definitions in the utilization analysis policy table 1200 to analyze utilization of each page. The utilization analysis unit 322 detects a problem on usability of the web application based on the result of the analysis on the utilization of the web pages. The page analysis unit 320, the operation analysis unit 321, and the utilization analysis unit 322 are executed in this order when the log analyzing module 231 is executed.
The log visualizing module 242 includes a utilization output unit 340, a threshold control unit 341, and a ranking calculation unit 342. The utilization output unit 340 outputs the result of analysis by the utilization analysis unit 322. The output in this example means to create data to be outputted in the form of a table or to be displayed on a window of the web application in overlay display. The threshold control unit 341 controls the thresholds for conditional expressions defined in the utilization analysis policy table 1200 (refer to the thresholds 1203 and 1212 in
Operation of the System
First, the web browser module 200 sends a request to show a web page to the web server device 120 (S421). Upon receipt of the page request from the client device 100 (S441), the web server module 220 invokes a web application 221 relating to the page request (S442). Next, the web application 221 performs processing responsive to the page request received at step S441 to create a response and transfers the created response to the function inserting module 222 (S443).
The function inserting module 222 inserts the operation log acquiring module 223 into the transferred response (S444). The step S444 can be performed with a response filtering function, such as the ServletFilter of Java EE™, included in the web server device 120.
Next, if the page request received at step S441 indicates start of a task (YES at S445), the function inserting module 222 proceeds to step S446. It generates a new task ID and sets the task ID to the Cookie of the response (S446). If the received page request indicates finish of a task (NO at S445 and YES at S447), the function inserting module 222 proceeds to step S448. It inserts a flag indicating finish of a task to the response (S448). Then, the function inserting module 222 sends the response to the client device 100 (S449).
The start and the finish of a task appearing at step S445 and S447 can be determined based on a request for the start or finish of the task or an event of pressing a specific button. The web server 120 continues processing from step S441 to S449 until the web server device 120 stops its operation (S450).
The processing from step S443 to S449 uses the response filtering function included in the web server device 120, but the web application 221 may include a program fragment to perform the above-described function in advance.
Upon receipt of the response from the web server device 120 (S422), the web browser module 200 invokes the script engine module 201 and initializes the operation log acquiring module 223 (S423). In the initialization at step S423, the web browser module 200 sets an event listener for monitoring events of user operations on the web browser module 200. The operation log acquiring module 223 captures operation log data of a user operation on the web browser module 200 and appends the log data to an operation log array for temporarily toring log data in the web browser module 200 (S424). Step S424 is repeated until an event of page transition occurs (S425).
Upon occurrence of an event of page transition (S425), the web browser module 200 sends values of the task ID, the page ID, the operation log 300, and the task-finished flag to the log analyzing server device 140 (S426). The client device 100 continues processing from steps S421 to S426 until the web application running on the client device 100 is finished (S427). In this embodiment, operation log data for a page is bunched into an operation log to be sent to the log analyzing server device 140, but the log data may be sent every time it is captured or in a bunch of a different unit.
The log server module 240 in the log analyzing server device 140 receives the operation log from the client device 100 and stores it in the current task operation log table 144 (S401). Subsequently, it ascertains whether the current task is finished with reference to the task-finished flag (S402). If the current task is finished (YES at S402), it performs current task finalization subroutine (S403). Details of step S403 will be described later. If the current task is not finished (NO at S402), the log server module 240 returns to step S401 and continues processing until the log analyzing server device 140 stops its operation (S404).
Current Task Finalization Subroutine
Before explaining the current task finalization subroutine, configurations of the current task operation log table 144, the route management table 700, and the operation log table 720 will be described.
As described previously, the current task operation log table 144 shown in
The task IDs 601 are identifiers for uniquely identifying tasks. The page IDs are identifiers for uniquely identifying pages. The operation log data 603 indicates operations on the pages identified with the page IDs 602.
The route management table 700 shown in
The route IDs 701 are identifiers for uniquely identifying routes indicating transitions of web pages. The routing information 702 indicates transitions of web pages in the routes identified with the route IDs 701.
The operation log table 720 shown in
The route IDs 721 are identifiers for uniquely identifying routes and the same identifiers as the route IDs 701 in the route management table 700 are used. The page IDs 722 are identifiers for uniquely identifying pages and the same identifiers as the page IDs 602 in the current task operation log table 144 are used. The operation log data 723 indicates operations on the pages identified with the page IDs 722.
In the case where the same page appears in a single route for a plurality of times, the page is regarded as different pages to manage the operation log data. In
Now, the current task finalization subroutine will be explained.
First, the log server module 240 retrieves all page IDs and operation logs from the current task operation log table 144 using the particular task ID as a key (S501). Next, the log server module 240 searches the route management table 700 for routing information including the same route as the page transitions (route) directed from the page IDs retrieved at step S501 and retrieves the route ID, if such routing information exists (S502).
Next, the log server module 240 determines whether the same route exists, in other words, whether step S502 is successful to retrieve a route ID (S503). If the determination indicates that the same route exists (YES at S503), the log server module 240 updates each operation log (each record in the operation log table 720) of the related route ID and page ID for all page IDs (S504).
If the determination at step S503 indicates that the same route does not exist (NO at S503), the log server module 240 generates a new route ID (S505). The log server module 240 appends the route ID and a list of page IDs to the route management table 700 (S506). Subsequently, the module 240 appends data relating the route ID, the page ID, and operation log data to the operation log table 720 for each of the page IDs appended to the route management table 700 (S507).
As described above, the log server module 240 updates operation log data in the operation log table 720 through the processing at step S504 and appends new routing information to the route management table 700 and the operation log table 720 through the processing from step S505 to step S507.
Page Analysis
Before explaining processing of the page analysis unit 320, the transition pattern detection rule table 900 will be described.
The transition pattern detection rule table 900 shown in
The transition pattern detection rules 902 shown in
The page analysis unit 320 in this embodiment refers to such a transition pattern detection rule table 900 and detects a specific transition pattern using a detection rule based on regular expressions. The manner to define detection rules and the method to detect a transition pattern are not limited to the regular expression basis but they may be a different manner to define detection rules and a different method to detect a transition pattern.
As described above, the page analysis unit 320 refers to the transition pattern detection rule table 900 and detects a specific transition pattern from a plurality of page transition patterns.
First, the page analysis unit 320 fetches a detection rule from the transition pattern detection rule table 900 shown in
If a detection rule exists (YES at S802) as a result of the determination, the page analysis unit 320 proceeds to step S803. If a detection rule does not exist (NO at S802), the page analysis unit 320 terminates this page analysis. This step S802 is performed for every detection rule stored in the transition pattern detection rule table 900.
At step S803, the page analysis unit 320 fetches one record of page transition log (the routing information 702 in
If a record of a page transition log exists (YES at S804) as a result of the determination, the page analysis unit 320 proceeds to step S805. If no record of page transition log exists (NO at S804), it returns to step S801 to fetch the next detection rule. This step S803 is performed for every page transition log managed in the route management table 700.
At step S805, the page analysis unit 320 applies the detection rule fetched at step S801 to the page transition log fetched at step S803 to acquire a list of matching segments of the page transition log (S805). In this description, a segmental transition log is a page transition log having a transition pattern matching with a detection rule. The processing at step S805 will be specifically explained with reference to
Then, the page analysis unit 320 determines whether a matching segmental transition log exists (S806). If a matching segmental transition log exists (YES at S806) as a result of the determination, the page analysis unit 320 proceeds to step S807. If no matching segmental transition log exists (NO at S806), the page analysis unit 320 returns to step S803 and fetches the next record of page transition log.
At step S807, the page analysis unit 320 relates transition patterns to links to the operation log table 720 (
Through the processing explained above, the page analysis unit 320 obtains segmental transition logs matching with a detection rule and operation logs for the pages that constitute the segmental transition logs.
First, the page analysis unit 320 creates a finite automaton from the detection rule fetched at step S801 in
The page analysis unit 320 determines whether the state of the finite automaton is valid (S1604). If the state of the finite automaton is determined to be valid (YES at S1604), the page analysis unit 320 proceeds to step S1605.
If the state of the finite automaton is determined to be invalid (NO at S1604), the page analysis unit 320 proceeds to step S1609 to reset the state of the finite automaton (S1609), and if the next URL exists (YES at S1608), the page analysis unit 320 fetches the next URL from the URL list (S1610) to proceed to step S1603 and repeats the comparison.
If the state of the finite automaton turns to “accept” at step S1605 (YES at S1605), the page analysis unit 320 registers a list of matching URLs as a segmental transition log (S1606), resets the finite automaton (S1607), and if the next URL exists (YES at S1608), fetches the next URL from the URL list (S1610). Then, it proceeds to step S1603 to repeat the comparison.
Log Per Transition Pattern Management Table 1000
The transition pattern table 1010 (
The operation log per transition pattern management table 1020 (
Operation Analysis
Utilization Analysis
If the determination indicates that the fetched record meets the analysis conditions in the utilization analysis policy table 1200 (YES at S1103), the utilization analysis unit 322 extracts the result of the analysis and appends it to the analysis result list (S1104).
Subsequently, the utilization analysis unit 322 determines whether the transition pattern table 1010 includes any unprocessed record (S1105). As a result, if the transition pattern table 1010 includes an unprocessed record (YES at S1105), it returns to step S1101 as there exists a record which has not been processed yet, and processes the next record.
Through repeating steps from S1101 to S1105, utilization analysis is performed on all records in the transition pattern table 1010 and a list of problems can be obtained.
The utilization analysis policy table 1200 shown in
For example, according to the first row of the utilization analysis policy table 1200, if the conditions that the rate of rerouting is 30% or more and the staying time at a back step is three seconds or less are met, the branch step (b) is the target of improvement and a modification is desired to solve the points of improvement 1222.
For example, in the case of transitions among pages shown in
The exemplary output shown in
As explained above, as to analysis work which has been difficult in listing problems because of extensive evaluation metrics, this embodiment achieves automatic listing of problems, so that the analysis time can be significantly reduced.
The foregoing embodiment has explained analysis of a web application including a workflow definition by way of example; however, this invention can analyze web applications without explicit workflow definitions as well. One way is analysis based on information on page transitions as indicated in
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